1. Technical Field
The present invention relates to a method for processing graphic data, and more particularly to a method for processing graphic data in a laser printer capable of improving an effect of processing the graphic data.
2. Related Art
A printer is an image formation device which receives data from a host computer and then forms a corresponding image onto a recordable medium such as a sheet of paper.
In a laser printer, print data such as document data or image data are received from external equipment such as a host computer or a personal computer to develop the print data into printable bit image data. The developed bit image data are stored into a print image buffer. Then, a laser beam corresponding to bit image data of one raster read out from the print image buffer is emitted from a laser diode to perform a main scanning operation, thereby forming an electrostatic latent image on a photosensitive drum for every dot line. Thereafter, toner is attached to the electrostatic latent image on the photosensitive drum and then transferred onto a recordable medium such as a sheet of paper. The toner on the recordable medium is heated by a fixing heater of a fixing device to fix the toner on the recordable medium, thereby completing a print process. Laser printers are also referred to as electrophotographic printers.
In order to reduce the memory capacity of memory hardware required, some laser printers today are using a banded, or partial page, print image buffer approach in which image data of one page are divided in smaller plural bands that are imaged as the page is being printed, and two bit map memories, referred to as band buffers, which are alternately used to write and read the image data portions. In other words, a page of graphic data is divided into a plurality of bands of data. The printer will print data corresponding to the graphic data onto a recordable medium band by band.
Multimedia systems that are driven to present combinations of moving and still pictures, sound, music, and words, are pervasive in the industrialized world, especially in computers or in other entertainment appliances. Concurrent with the development of multimedia computer systems, peripheral equipment including image formation equipment such as printers, have been incrementally modified to provide various functions. A multi-tasking system, employing an ink-jet mechanism and serving as a facsimile and scanner, can be coupled to an external personal computer that performs a user-selected program and generates print data. The multi-tasking system can either receive data from the personal computer or scan data printed on the exposed surface of one or more documents. Multi-tasking systems include a scanner such as a laser flatbed or sheetfed scanner, for reading information existing on a document by scanning the document. With a sheetfed laser scanner, the scanner remains in a fixed state while the document bearing the information is moved in a vertical direction during laser scanning of its exposed surface. With a flatbed laser scanner, a laser beam is swept across a flat plate by the scanner modulated by video signals from a similar reading system or by digital signals generated by a computer.
Computer systems are information handling systems that are utilized by many individuals and businesses today. A computer system can be defined as a microcomputer that includes a central processing unit (CPU), a volatile memory, a non-volatile memory such as read only memory (ROM), a display monitor, a keyboard, a mouse or other input device such as a trackball, a floppy diskette drive, a compact disc-read only memory (CD-ROM) drive, a modem, a hard disk storage device, and a printer. A computer system's main board, which is a printed circuit board known as a motherboard, is used to electrically connect these components together.
Recently, office automation instruments such as a printer, a scanner, and a facsimile device are widely utilized. Respective office automation devices having a high performance are developed to expand a inherent function thereof. It is intended to produce more expensive instrument.
On the other hand, office automation instruments which are used to separately are developed to be integrated with each other in one piece, resulting in decreasing the economical burden of user. It is referred to as a combined office automation instrument or a multi-functional office device.
I have found that laser printers can be slow during print operations. Efforts have been made to improve laser printers.
Exemplars of recent efforts in the art include U.S. Pat. No. 5,729,668 for OPTIMIZED HARDWARE COMPRESSION AND DECOMPRESSION ARCHITECTURE FOR USE BY AN IMAGE PROCESSOR IN A LASER PRINTER issued to Claflin et al., U.S. Pat. No. 5,615,314 for INTERFACE FOR PROVIDING RASTERIZED DATA TO AN IMAGING DEVICE issued to Schoenzeit et al., U.S. Pat. No. 5,481,656 for ACCESSORY CONTROL DEVICE AND INFORMATION PROCESSING METHOD issued to Wakabayashi et al., U.S. Pat. No. 5,444,830 for METHOD AND APPARATUS FOR CONTROLLING EXPOSURE AND TRANSFERENCE IN AN ELECTROPHOTOGRAPHIC RECORDING APPARATUS issued to Oh et al. U.S. Pat. No. 4,992,956 for APPARATUS FOR ASSEMBLING DATA FOR SUPPLY TO A SCANNING OUTPUT DEVICE issued to Kaku et al., U.S. Pat. No. 4,991,108 for DATA PROCESSOR PRINTER ARRANGEMENT issued to Hamilton, U.S. Pat. No. 5,586,229 for BAND PRINTING METHOD FOR PREVENTING BAND OVERRUN ERROR IN PAGE PRINTER issued to Kim et al., U.S. Pat. No. 5,737,602 for IMAGE FORMING APPARATUS USING BAND BUFFERING SYSTEM AND PRINTING METHOD THEREOF issued to Lee, and U.S. Pat. No. 4,918,624 for VECTOR GENERATOR SCAN CONVERTER issued to Moore et al.
While these recent efforts provide advantages, I note that they fail to adequately provide an enhanced method for processing graphic data in a laser printer.